In order to install & use it on Blogger, follow the below simple steps:
1) Go to your Template Layout->Download your template as a backup first
2)Now click Edit HTML for Layout & then paste the below code in your Template before your </head> tag ends. Note this is pointing to the Latest released version v2.1.364; older versions can be found at: http://alexgorbatchev.com/pub/sh/

Thanks for the article! I was having problems to get the syntaxhighligghter to work properly with blogger. The other articles I found were more complicated and didn't work 100%. Your instructions are very simple and easy to follow, and it works perfect!

Thanks for this quick and easy guide! Works great for me. Just one small point I was stumbling:Instead of just copy&paste the code to the template, the list of brushes should be edited to the one actually needed. I was searching for a wile why the brush 'shell' wasn't working. And removing not needed brushes let the page load quicker (it is to slow any way ;-) ).